Process of combusting coal mixtures in furnaces.



PATENTED JULY 3, 1906.

G. MIELENHAUSEN.

. PROCESS OF OOMBUSTING COAL MIXTURES IN FURNACES.

APPLICATION FILED D1309. 1905.

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GEORGE MIELENHAUSEN, OF NEW YORK, N. Y.

PROCESS OF COMBUSTING COAL MIXTURES IN FURNACES.

Specification of Letters Patent.

Patented July 3, 1906.

Application filed December 9, 1905. Serial No. 291,016.

To all wit/mt it nuty concern:

Be it known that I, GEORGE MIELENI-IAU- sEN, a citizen of the United States of America, and a resident of New York, in the county and State of New York, have invented certain new and useful Improvements in Processes of Combusting Coal Mixtures in Furnaces, of which the following is a specification.

This invention has reference to improvements in a novel process of combusting coal mixtures in furnaces.

It is the special object of my invention to provide a new process by means of which it is rendered possible to use within city limits a considerable percentage of soft coal, coal-dust, or coke-dust, whereby a great saving is effected.

As is well known, heavy, dense, and black smoke will issue from a chimney when soft coal or coal-dust is burned. Such black dense smoke is obnoxious, disagreeable, and blackens up everything in the neighborhood, whereby damage is done and great inconvenience caused. For this reason soft coal could be burned only in certain small places or isolated plants; but its use was prohibited in cities. Its use in cities was allowed solely during strikes in the anthracite coal regions when hard coal could not be bought in the market.

My novel process renders it possible to burn a large percentage of soft coal and coaldust at any time, because by its application no black dense smoke will issue from chimneys, and only the usual li ht and white smoke will issue from the ciimneys, as if hard coal solely were burned. The process, however, is particularly valuable during strike periods, and in cases of necessity soft coal alone may be burned without any inconvenience or damage to the neighbors of a factory in a city.

A special feature of my invention is that the burning coal mixture containing coal-dust is kept down by a curved envelop or mantle of steam under pressure. This envelop of steam is of semitubular shape. It is consequently highest in the center above the burning coal, where the heat is most intensive and the combustion of the coal particles most complete. The combustion-gases are there fore lightest in this zone and escape easily through the top zone of the curved steamenvelop. Near and at the side walls of the furnace the combustion is not so rapid and intense, and unburned coal-dust is contained in the space above same. This coal-dust is held down by the curved steam-envelop, together with the heavy combustion-gases, in the longitudinal central zone. The two side zones of the steam-mantle extend gradually farther down and keep the dust down on the body of the burning coal mixture.

It is clear from the above that no rapid combustion of the coal mixture is effected. Hence the great saving by this process and that no conducting away of fuel-gases impregnated with coal-dust is brought about, whereby a loss of combustible material is entailed. On the contrary, all the coal-dust and combustible fuel-gases are kept down and most economically used up.

My process may be employed in all kinds of furnaces.

In order to make the process more easily understood, a furnace is diagrammatically illustrated in the accompanying drawings, in which Figure 1 represents a furnace in side elevation and partly in section. Fig. 2 is an end view of the steam-blower, and Fig. 3 is a top plan of same.

Similar letters of reference denote like parts in all the three figures.

In the drawings, 9 represents the grating on which the coal mixture 0 is located which is introduced through the door (1. Right above the door (1 there is a steam-pipe p, which is provided with a steam-valve o. The steam-pipe runs through the front wall of the furnace, and a blower b is attached thereto within said furnace. The blower consists of a short tube t and the broad short blowerbody I). The blower-body is hollow and curved, as shown in Fig. 2. At the front or inner end the blower has a curved slot 8, through which the compressed steam issues, whereby a curved steam envelop or mantle is formed. This steam-envelop strikes against the rear brick wall w of the fire-box. The steam-pipe p connects with a boiler, and the steam is under considerable pressure.

The coal mixture which I prefer to use consists of soft or other bituminous coal with peanut-coal of the anthracite kind and coaldust. If coke-dust is at disposal, same may be mixed in in place of coal-dust. In case of emergency soft coal and coal-dust alone may be used. Assuming now that a steam-engine of seventy-five actual horse-power is to be run by means of my novel process, then IIO about nineteen hundred pounds of coal mixture are required per day. This mixture will contain about five hundred pounds of soft coal and equal parts of peanut-coal and coaldust, together fourteen hundred pounds. When the fire is started, the blower is turned on, whereby a semitubular envelop or mantle of steam is formed about the burning coal mixture. The curved steam-envelop keeps the coal-dust down on the burning coal, and' the heavy combustion-gases are likewise kept down and economically burned up. The light combustion gases, however, pass through the curved steam envelop or mantle, particularly through its longitudinal central zone, as above explained. It may be stated here that a rather skilful fireman is required for attending to such a fire but less labor is required as compared with the employment of the old methods. The fire does not need any cleaning during a run of ten to twelve hours. A few times stirring during the day will be suflicient to keep up a bright fire, and the less pokering and stirring is done the better it is for the fire, because too much of either will destroy same. Only two of the usual ash-cans full of ashes remain per day, so complete and economical is the combustion of the coal mixture. Thus a saving of one-fourth to one-third is effected by the use of my process. It is further of great convenience when strikes are occurring in the anthracite coal regions and is then used without any damage or inconvenience to the neighbors of factories in cities.

Having thus described my invention, I claim as new and desire to secure by Letters Patent 4 1. The process of combusting economically in furnaces coal mixtures containing soft coal and coal-dust which consists in enveloping the burning coal in a semitubular mantle of compressed steam and retaining thereby the fine coal particles and heavy combustiongases on the burning coal.

2. The process of combusting economically in furnaces coal mixtures containing soft coal and coal-dust which consists in igniting the coal mixture and passing over the burning coal a semitubular envelop or mantle of steam under pressure which is highest in the center above the burning coal where the heat is most intense and lowest on the side walls of the furnace whereby the fine coal particles and heavy combustion-gases are kept down on the burning coal while the light combustiongases escape through the central and highest zone of the said semitubular envelop of steam.

Signed at New York, N. Y., this 8th day of December, 1905.

GEORGE MIELENHAUSEN.

T/Vitnesses:

LUDWIG K. BoHM, JAMEs J. ASTA-RITA. 

